Air chuck



Jan. 155, 1946. E. A. F. REDMER AIR CHUCK Filed Feb. 2. 1944 ATTwm EY vfill/H7727]? ZUM/v AF 175171751? Patented Jan. 15, 1946 UNITED .STATES PATENT OFFICE AIR CHUCK Edwin A. F. Redmer, Chicago, Ill.

Application February 2, 1944, Serial No. 521,004

7 Claims.

7 The invention relates to improvements in chucks and more particularly to chucks of a kind having fluid pressure actuated reciprocable means operable to close the jaws of a collet contained therein. Y

The present invention is concerned with improvements in the structural organization of a fluid pressure operated chuck of the character shown and claimed in my Patent No. 2,338,060, dated December 28, 1943. The chuck herein disclosed and embodying features of the present invention is of a kind intended to be rested firmly upon the bed of an automatic machine, such as for example, a drill press, in axial alignment with the tool of the machine so as to locate and hold small parts firmly in place for accurate tooling. Chucks of this character necessarily must be capable of gripping and releasing a part rapidly otherwise much valuable production time is lost, and further the chuck must automatically locate the part with respect to the tool preferably during the gripping operation. It is therefore an'object of the present invention to provide an improved chuck of the kind referred to which is not expensive to manufacture, is very easy to assemble and disassemble should repair or replacement of any of its parts become necessary, and which is very efiicient in use and highl practical.

The chuck of my previous invention identified hereinabove embodies a structure which necessie tates a relatively large housing or body and-as a consequence thechuck is heavy and its use on automatic machines having an extremely small bed often is exceedingly diflicult of accomplishment and in some instances impossible. It is therefore another object of the present invention to provide a chuck oi the kind exemplified herein-which is extremely compact in its structural organization and hence easily enclosed within a housing or body of such size as to render the assembly light in weight and especially suited for use in association with machines having small beds.

Other and further objects. of the present invention will be apparent from the following description'and claims and are illustrated in the accompanying drawing which, by way of illustration, show a preferred embodiment and the principle thereof and which is considered to be thebest mode for applying that principle. Other embodiments of the invention embodying. the same or, equivalent principle may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims,

- In the drawing:

'Fig. 1 is a top plan view of the chuck embodying features of the present invention, showing a portion of the cap' ring broken away.

Fig. 2 is an axial sectional view of the chuck. Fig. 3 is a bottom plan view of the chuck. The fluid pressure operated chuck exemplified in the accompanying drawing is wholly enclosed 5 within ahollow body, as at H, having an external base flange l2 at the lower end of a circular outer wall IS. The wall merges into a relatively thick top wall it having a large axial opening I5 surrounded at its outer end by an annular flange I6. An internal circular wall [1, cast integral with and extending downwardly from the inside face of the top wall l4, provides an extension for the axial opening l5 and said wall is spaced concentrically from the outer wall l3 so as to thereby provide a circular space is for a purpose to be described presently. The inner wall I! terminates short of the bottom of the hollow body and its bottom edge has a plurality of pairs of depending ears I!) preferably cast integral therewith. These pairs of ears, which are for a purpose to be explained presently, are circumferentially spaced apart and any suitable number of pairs such as for example, two, three or the four pairs illustrated, may be provided. It may be desired to attach the chuck to a lathe and for this purpose internal threads are provided at the open bottom of the hollow body I l.

A sleeve 2| is slidably disposed in the axial opening l5 and the upper margin of its inside circumferential face is inclined outwardly uniformly to provide an annular cam surface 22. A collet 23 is slidably disposed in the sleeve 2|. The collet 23 includes a bearing portion 24 at its lower end which has a free sliding fit within the sleeve 2| and a plurality of jaws 25 formed at its upper end by longitudinal slots 26. The outside face of the end of the collet having the jaws 25 is tapered outwardly as at 21, to have matching engagement with the annular. cam surface 22 in the sleeve and it is circumferentially shouldered at its free end as at 28 to fit snugly into an axial opening 29 formed in a retaining cap 30 screwed onto the annular body flange I6.

It should be apparent that when the sleeve 2| is located in the position shown in Fig. 2, the collet 23v is firmly held against movement relative to the body H and that should the sleeve be moved longitudinally upwardly over the collet, the collet jaws 25 will be contracted radially because of the camming action thereon resulting from the matched tapered surfaces at 22 and 21. Longitudinal movement of the sleeve is effected by fluid pressure means acting upon the bottom end of said sleeve.

As shown, a circular piston 3| is arranged within the circular space l8 and an inlet for liquid pressure, such as air, is provided at the upper end of said space, as through a nipple 32, so that upon the admittance of air under pressure 60 into the space 18 above the piston 3|, said piston is forced downwardly.

one end portion 331: extended beneath the sleeve; 2! thereby providing the sole support to limit downward movement of said sleeve. The other ends 33b of said levers project into'the annular space l8 beneath the piston 3| and said piston is fitted with circumferentially spaced contact 5 pins 34 each of which is in alignment with and intended to rest upon a lever end 33b.

'- -Accordingly, downward movement of the piston ;auses the lever ends 3311 to be moveddownw-ardly' so as to thereby raise their opposite ends 331% and carry the sleeve 2L upwardly. over the jaws-25 to contract them. When liquid pressure on the piston is relieved, the inherent tendency. of; the jaws to retum tol their initial expanded position forces the sleeve '21 downwardly, thus rocking the levers -33 in an opposite. direction andelevaiting the piston 31. Y T V w it should be evidentt'l-iat "the opening and chasing-oi the jaws 2:4. is instantaneous in response to admittance or relief of liquid pressure on the piston'an'd that the jaws areicapableaoi being contraoted around any obj-ectplaced thereinwith suificient firmness to retain such 'objectin position to be worked upon. .Furthen, the construct-ion andorganizatiori of thepartsis such that a very practical, compact and durable. chuck is provided which does-. not require a large areav upon which toi re'st and hence is. very "useful. L I'l-aimrf v i :1. 'itniachuck, a hollow body havinga circular internalwall-surrounding axial opening, a, ci-r.-. cuiar airs-chamber. in said; body surrounding-said internal. wall, a sleeve slidably disposed in said opening, a collet disposed'ila sai'd. sleeve, means securing" the collet. against movement "in said may, coiioperating means: between. thesleeve and collet 'for cl'osingfthe jawsrof-=said colletwhen the sleeve is rnoved; inone: direction and for permit-, orig the opening. :15 said jaws when the sleeve mo ves :m th'e opposite. direction, and meansa for moving the sleeverl'n one direction onlyincludinglevers pi vota'lly mouritedand pressure meansacting on one;

levers tor morving the same. 2 a -2; in a: chuck, a hollow body having-a. wall surroimding an axial opening, a. C11! end of cular'air chamher said body-surroundhig "said wallg a'sleeve slidably disposed in saidopen-ing; a coliet disposedtin said sleeve, means securing the collet against movement in :said body, coaoperau ing mans between the 'sl'eeveltand colletfior-zclosme fihe'ijaws' ofsa'id collet when thexsl'eeve. is moved in. one direction and for permitting the opening pf sai'd: jaws when the sleevelmoviesin the opposite. idirection, and means 'ior moving the sleeve in 'on'e direction only" including 'leve'rs. piv: otal' ly mounted 'inu's'aiid 'body andifluid pressure moan'sioperable inithe air cham'berrranda acting on onean (if the leve'rs tor movingthe same;

35111 a than, a 'hollow body having a circular internal wall surrounding an opening, a circular air-"ch niber in said body surroundingsaidainternal wall, a sleeveslidably disposed-in said-open:- ing,' a collet disposed in' said sleeve, m'eans securing t e o'ollet against movement sai'd bodg; (lo-operating. means between the-sleeve and; collet for closing the jaws ofsaLid oollet when thesleeve is moved in one direction anertr per'mimng the on said internal: wall opening of said jaws when the sleeve moves in the opposite direction, a plurality of lovers pivotally mounted on said internal wall each having end ooi-aeting -wwith said sleeve, and a piston 5 in said air chamber co'sacting with "the other ends of said levers for moving the same to move lithe sleeve in a direction to close said jaws.

m In a chuck, a body having concentric inner and outer circular walls defining an annular 10 space, a wall connecting said inner and outer walls, a sleeve slidably disposed within said inner wall, a collet disposed in said sleeve, a cap firmly securing the collet against movement in said body one direction, co-operating means between the 15 sleeve and. collet for closing the ,jaws-oiv-said collet. when thesleeve ismoved in one direction and for permittnig-the-opening of the. jaws when the sleevetis moved the po ite d rect on, at least one lever pivotally mounted on said internalwall havin a end co stin with sai sleeve! and a ci ar piston oes ehle he space-be ween aid A w econ iles, with the other and oi a d: ever -2 mo n the same. t mere le a ,ehuq l Win h r-11 concen ri inne and outer: c rc a w s n ng an a nular sn ea-a tonwel qw e ct es; fii nner nd; W 91? a sl eve s idab ros d ith n aid nner wa o et d pose a lee e, ans se sla the-c lle ae in tmo mentinaai fin col-operating .meang-between the sleeve, and QQla let; to prevent movement oi th v oolletin the di; at os f -s eeve and orelo 'ins hel-iawsef.

Said; c l et when he ere move n ne d3. moti n and? mr rem t in th o enin at. he

sinu wh n. he sleeve is moved i t e p s te d e tion a plu a i f "l vers nivcta v mou ted aid n ern w ll een ov ne a e d. loect; with saidslleeve, a circular piston, operable n. the a e-be ween saidnner and o er a ls; Q0?- c' ins w th he o he nd of aid leversiczmovi s sama qim ve the le v in adirecti n, tea e a 'dia si Lei /ch t, abody h vi g a ci cul r pen: ts; slera s dah v disposed said pen na a collet d 'su seo. n, saidwamwns securing the o let a ainst m yemerit i said. 1 .com,v liq-open t" a e. n1 b we e he, a d. one or whe the l eve.

rem tt ng th H j n e n n he pp i l llemb r, 15 6 m urrount iia M t aid' peninaa i ten n .4 1:.; and m ans s;

se ze nane dir cti n unseen U .preme itjqi hej eten nre n e e fluid pressure means ac ing upon saidpiston.

'1' ac l s ls. a ba ir a ine a e wa i t eislee e lida rr i e0 posed I rd opening, aqcolleedisposedinsaid le v me as same the c l t sa f 1 b ,3 m nda i m a esn no n the collet; for closing-the jaws; chenth sl eve em f f ne ting the-'openin"g; of said v h ym v drmf o e direc fon an annular; chamberin said body hi a a ne if sg al g it im ercircular in saigi airchamber; and-"means operatively connecting the sleeve ari'd said pls ton for moving the sleeve in one directioni to close said jaws upon movement:of'-the"piston in responsete'fiuid pressuremeans acting'luponis'aid fiitbm '7 hat-anatomy 1 

